SQLite

*/
static void fts5SegIterReverse(Fts5Index *p, Fts5SegIter *pIter){
  Fts5DlidxIter *pDlidx = pIter->pDlidx;
  Fts5Data *pLast = 0;
  int pgnoLast = 0;

  if( pDlidx ){



    int iSegid = pIter->pSeg->iSegid;
    pgnoLast = fts5DlidxIterPgno(pDlidx);
    pLast = fts5DataRead(p, FTS5_SEGMENT_ROWID(iSegid, 0, pgnoLast));



  }else{
    int iOff;                               /* Byte offset within pLeaf */
    Fts5Data *pLeaf = pIter->pLeaf;         /* Current leaf data */

    /* Currently, Fts5SegIter.iLeafOffset (and iOff) points to the first 
    ** byte of position-list content for the current rowid. Back it up
    ** so that it points to the start of the position-list size field. */

  Fts5SegWriter *pWriter, 
  int iSegid
){
  memset(pWriter, 0, sizeof(Fts5SegWriter));
  pWriter->iSegid = iSegid;

  pWriter->aWriter = (Fts5PageWriter*)fts5IdxMalloc(p, sizeof(Fts5PageWriter));

  if( fts5WriteDlidxGrow(p, pWriter, 1) ) return;
  pWriter->nWriter = 1;
  pWriter->nDlidx = 1;
  pWriter->aWriter[0].pgno = 1;
  pWriter->bFirstTermInPage = 1;
}

static void fts5WriteInitForAppend(

        int iOff = 0;

        writer.bFirstRowidInPage = 0;

        /* The entire doclist will not fit on this leaf. The following 
        ** loop iterates through the poslists that make up the current 
        ** doclist.  */
        while( p->rc==SQLITE_OK && iOff<nDoclist ){
          int nPos;
          int nCopy;
          int bDummy;
          iOff += getVarint(&pDoclist[iOff], (u64*)&iDelta);
          nCopy = fts5GetPoslistSize(&pDoclist[iOff], &nPos, &bDummy);
          nCopy += nPos;
          iRowid += iDelta;

            fts5BufferSafeAppendBlob(pBuf, &pDoclist[iOff], nCopy);
          }else{
            /* The entire poslist will not fit on this leaf. So it needs
            ** to be broken into sections. The only qualification being
            ** that each varint must be stored contiguously.  */
            const u8 *pPoslist = &pDoclist[iOff];
            int iPos = 0;
            while( p->rc==SQLITE_OK ){
              int nSpace = pgsz - pBuf->n;
              int n = 0;
              if( (nCopy - iPos)<=nSpace ){
                n = nCopy - iPos;
              }else{
                n = fts5PoslistPrefix(&pPoslist[iPos], nSpace);
              }

}

/*
** Flush any data stored in the in-memory hash tables to the database.
*/
static void fts5IndexFlush(Fts5Index *p){
  /* Unless it is empty, flush the hash table to disk */
  if( p->nPendingData ){
    assert( p->pHash );
    p->nPendingData = 0;
    fts5FlushOneHash(p);
  }
}

  assert( p->rc==SQLITE_OK );

  /* Allocate the hash table if it has not already been allocated */
  if( p->pHash==0 ){
    p->rc = sqlite3Fts5HashNew(&p->pHash, &p->nPendingData);
  }

  /* Flush the hash table to disk if required */
  if( iRowid<=p->iWriteRowid || (p->nPendingData > p->nMaxPendingData) ){
    fts5IndexFlush(p);
  }
  p->iWriteRowid = iRowid;
  return fts5IndexReturn(p);
}

  for(pDlidx=fts5DlidxIterInit(p, 1, iSegid, iLeaf);
      fts5DlidxIterEof(p, pDlidx)==0;
      fts5DlidxIterPrev(p, pDlidx)
  ){
    i64 iRowid = fts5DlidxIterRowid(pDlidx);
    int pgno = fts5DlidxIterPgno(pDlidx);

    assert( fts5DlidxIterPgno(pDlidx)>iLeaf );
    cksum2 += iRowid + ((i64)pgno<<32);
  }
  fts5DlidxIterFree(pDlidx);
  pDlidx = 0;

  if( p->rc==SQLITE_OK && cksum1!=cksum2 ) p->rc = FTS5_CORRUPT;

    ** ignore this b-tree entry. Otherwise, load it into memory. */
    if( iter.iLeaf<pSeg->pgnoFirst ) continue;
    iRow = FTS5_SEGMENT_ROWID(pSeg->iSegid, 0, iter.iLeaf);
    pLeaf = fts5DataRead(p, iRow);
    if( pLeaf==0 ) break;

    /* Check that the leaf contains at least one term, and that it is equal
    ** to or larger than the split-key in iter.term.  Also check that if there
    ** is also a rowid pointer within the leaf page header, it points to a
    ** location before the term.  */
    iOff = fts5GetU16(&pLeaf->p[2]);
    if( iOff==0 ){
      p->rc = FTS5_CORRUPT;
    }else{
      int iRowidOff;
      int nTerm;                  /* Size of term on leaf in bytes */
      int res;                    /* Comparison of term and split-key */

      iRowidOff = fts5GetU16(&pLeaf->p[0]);
      if( iRowidOff>=iOff ){
        p->rc = FTS5_CORRUPT;
      }else{
        iOff += fts5GetVarint32(&pLeaf->p[iOff], nTerm);
        res = memcmp(&pLeaf->p[iOff], iter.term.p, MIN(nTerm, iter.term.n));
        if( res==0 ) res = nTerm - iter.term.n;

        if( res<0 ) p->rc = FTS5_CORRUPT;
      }
    }
    fts5DataRelease(pLeaf);
    if( p->rc ) break;


    /* Now check that the iter.nEmpty leaves following the current leaf
    ** (a) exist and (b) contain no terms. */
    for(i=1; p->rc==SQLITE_OK && i<=iter.nEmpty; i++){
      pLeaf = fts5DataRead(p, iRow+i);
      if( pLeaf && 0!=fts5GetU16(&pLeaf->p[2]) ){
        p->rc = FTS5_CORRUPT;

      sqlite3Fts5BufferSet(&rc, &pCsr->term, nTerm, (const u8*)zTerm);
      memset(pCsr->aVal, 0, sizeof(pCsr->aVal));
      memset(pCsr->aCnt, 0, pCsr->nCol * sizeof(i64));
      memset(pCsr->aDoc, 0, pCsr->nCol * sizeof(i64));
      pCsr->iCol = 0;

      assert( pTab->eType==FTS5_VOCAB_COL || pTab->eType==FTS5_VOCAB_ROW );
      while( rc==SQLITE_OK ){
        const u8 *pPos; int nPos;   /* Position list */
        i64 iPos = 0;               /* 64-bit position read from poslist */
        int iOff = 0;               /* Current offset within position list */

        rc = sqlite3Fts5IterPoslist(pCsr->pIter, &pPos, &nPos);
        if( rc==SQLITE_OK ){

          if( pTab->eType==FTS5_VOCAB_ROW ){
            while( 0==sqlite3Fts5PoslistNext64(pPos, nPos, &iOff, &iPos) ){
              pCsr->aVal[1]++;
            }
            pCsr->aVal[0]++;
          }else{
            int iCol = -1;
            while( 0==sqlite3Fts5PoslistNext64(pPos, nPos, &iOff, &iPos) ){
              int ii = FTS5_POS2COLUMN(iPos);
              pCsr->aCnt[ii]++;
              if( iCol!=ii ){
                pCsr->aDoc[ii]++;
                iCol = ii;
              }
            }
          }

          rc = sqlite3Fts5IterNextScan(pCsr->pIter);
        }
        if( rc==SQLITE_OK ){
          zTerm = sqlite3Fts5IterTerm(pCsr->pIter, &nTerm);
          if( nTerm!=pCsr->term.n || memcmp(zTerm, pCsr->term.p, nTerm) ) break;
          if( sqlite3Fts5IterEof(pCsr->pIter) ) break;
        }
      }
    }
  }

  if( pCsr->bEof==0 && pTab->eType==FTS5_VOCAB_COL ){
    while( pCsr->aCnt[pCsr->iCol]==0 ) pCsr->iCol++;
    pCsr->aVal[0] = pCsr->iCol;

  CREATE VIRTUAL TABLE t1 USING fts5(x);
  INSERT INTO t1(t1, rank) VALUES('pgsz', 32);
  WITH ii(i) AS (SELECT 1 UNION SELECT i+1 FROM ii WHERE i<100)
  INSERT INTO t1 SELECT rnddoc(10) FROM ii;
}
set mask [expr 31 << 31]

if 1 {

# Test 1:
#
#   For each page in the t1_data table, open a transaction and DELETE
#   the t1_data entry. Then run:
#
#     * an integrity-check, and

  } 1

  do_execsql_test 2.$i.4 {
    ROLLBACK;
    INSERT INTO t1(t1) VALUES('integrity-check');
  } {}
}

}

#-------------------------------------------------------------------------
# Test that corruption in leaf page headers is detected by queries that use
# doclist-indexes.
#
set doc "A B C D E F G H I J "
do_execsql_test 3.0 {
  CREATE VIRTUAL TABLE x3 USING fts5(tt);
  INSERT INTO x3(x3, rank) VALUES('pgsz', 32);
  WITH ii(i) AS (SELECT 1 UNION ALL SELECT i+1 FROM ii WHERE i<1000) 
  INSERT INTO x3 
  SELECT ($doc || CASE WHEN (i%50)==0 THEN 'X' ELSE 'Y' END) FROM ii;
}

foreach {tn hdr} {
  1 "\x00\x00\x00\x00"
  2 "\xFF\xFF\xFF\xFF"
  3 "\x44\x45"
} {
  set tn2 0
  set nCorrupt 0
  set nCorrupt2 0
  foreach rowid [db eval {SELECT rowid FROM x3_data WHERE rowid>10}] {
    if {$rowid & $mask} continue
    incr tn2
    do_test 3.$tn.$tn2.1 {
      execsql BEGIN

      set fd [db incrblob main x3_data block $rowid]
      fconfigure $fd -encoding binary -translation binary
      set existing [read $fd [string length $hdr]]
      seek $fd 0
      puts -nonewline $fd $hdr
      close $fd

      set res [catchsql {SELECT rowid FROM x3 WHERE x3 MATCH 'x AND a'}]
      if {$res == "1 {database disk image is malformed}"} {incr nCorrupt}
      set {} 1
    } {1}

    if {($tn2 % 10)==0 && $existing != $hdr} {
      do_test 3.$tn.$tn2.2 {
        catchsql { INSERT INTO x3(x3) VALUES('integrity-check') }
      } {1 {database disk image is malformed}}
    }

    execsql ROLLBACK
  }

  do_test 3.$tn.x { expr $nCorrupt>0 } 1
}

proc do_fb_test {tn sql res} {
  set res2 [lsort -integer -decr $res]
  uplevel [list do_execsql_test $tn.1 $sql $res]
  uplevel [list do_execsql_test $tn.2 "$sql ORDER BY rowid DESC" $res2]
}






# This test populates the FTS5 table containing $nEntry entries. Rows are 
# numbered from 0 to ($nEntry-1). The rowid for row $i is:
#
#   ($iFirst + $i*$nStep)
#
# Each document is of the form "a b c a b c a b c...". If the row number ($i)
# is an integer multiple of $spc1, then an "x" token is appended to the

      if {($i % $spc2)==0} { 
        lappend ydoc $rowid
        append doc " y" 
      }
    }
    execsql { INSERT INTO t1(rowid, x) VALUES($rowid, $doc) }
  }

  execsql COMMIT

  breakpoint
  do_test $tn.1 {
    execsql { INSERT INTO t1(t1) VALUES('integrity-check') }
  } {}
  
  do_fb_test $tn.3.1 { SELECT rowid FROM t1 WHERE t1 MATCH 'a AND x' } $xdoc
  do_fb_test $tn.3.2 { SELECT rowid FROM t1 WHERE t1 MATCH 'x AND a' } $xdoc
  
  do_fb_test $tn.4.1 { SELECT rowid FROM t1 WHERE t1 MATCH 'a AND y' } $ydoc
  do_fb_test $tn.4.2 { SELECT rowid FROM t1 WHERE t1 MATCH 'y AND a' } $ydoc
  
  do_fb_test $tn.5.1 { 
    SELECT rowid FROM t1 WHERE t1 MATCH 'a + b + c + x' } $xdoc
  do_fb_test $tn.5.2 { 
    SELECT rowid FROM t1 WHERE t1 MATCH 'b + c + x + y' } $ydoc
}


foreach {tn pgsz} {
  1 32
  2 200
} {
  do_execsql_test $tn.0 { 
    DROP TABLE IF EXISTS t1;
    CREATE VIRTUAL TABLE t1 USING fts5(x);
    INSERT INTO t1(t1, rank) VALUES('pgsz', $pgsz);
  }

  do_dlidx_test1 1.$tn.1     10 100 10000 0 1000
  do_dlidx_test1 1.$tn.2     10 10  10000 0 128
  do_dlidx_test1 1.$tn.3     10 10  66    0 36028797018963970
  do_dlidx_test1 1.$tn.4     10 10  50    0 150000000000000000
  do_dlidx_test1 1.$tn.5     10 10  200   0 [expr 1<<55]
  do_dlidx_test1 1.$tn.6      10 10  30    0 [expr 1<<58]
}

proc do_dlidx_test2 {tn nEntry iFirst nStep} {
  set str [string repeat "a " 500]
  execsql {
    BEGIN;
    DROP TABLE IF EXISTS t1;
    CREATE VIRTUAL TABLE t1 USING fts5(x);
    INSERT INTO t1(t1, rank) VALUES('pgsz', 64);
    INSERT INTO t1 VALUES('b a');

    WITH iii(ii, i) AS (
      SELECT 1,     $iFirst UNION ALL 
      SELECT ii+1, i+$nStep FROM iii WHERE ii<$nEntry
    )
    INSERT INTO t1(rowid,x) SELECT i, $str FROM iii;
    COMMIT;
  }

  do_execsql_test $tn.1 {
    SELECT rowid FROM t1 WHERE t1 MATCH 'b AND a'
  } {1}
  breakpoint
  do_execsql_test $tn.2 {
    SELECT rowid FROM t1 WHERE t1 MATCH 'b AND a' ORDER BY rowid DESC
  } {1}
}

do_dlidx_test2 2.1 [expr 20] [expr 1<<57] [expr (1<<57) + 128]

finish_test

    WITH ii(i) AS (SELECT 1 UNION ALL SELECT i+1 FROM ii WHERE i<200)
      INSERT INTO tt(rowid, x) 
      SELECT i, CASE WHEN (i%50)==0 THEN 'a a a a a a' ELSE 'a x a x a x' END 
      FROM ii;
  COMMIT;
}



do_faultsim_test 10.1 -faults oom-t* -body {
  db one { SELECT fts5_expr('a AND b NEAR(a b)') }
} -test {
  faultsim_test_result {0 {"a" AND ("b" AND NEAR("a" "b", 10))}} 
}

}


#do_faultsim_test 10.2 -faults oom-t* -body {
#  db one { SELECT fts5_expr_tcl('x:"a b c" AND b NEAR(a b)', 'ns', 'x') }
#} -test {
#  set res {[ns -col 0 -- {a b c}] && ([ns -- {b}] && [ns -near 10 -- {a} {b}]}
#  faultsim_test_result [list 0 $res]
#}



finish_test

# 2014 June 17
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#*************************************************************************
#
# This file is focused on OOM errors.
#

source [file join [file dirname [info script]] fts5_common.tcl]
source $testdir/malloc_common.tcl
set testprefix fts5fault5

# If SQLITE_ENABLE_FTS3 is defined, omit this file.
ifcapable !fts5 {
  finish_test
  return
}

#-------------------------------------------------------------------------
# OOM while creating an FTS5 table.
#
do_faultsim_test 1.1 -faults oom-t* -prep {
  db eval { DROP TABLE IF EXISTS abc }
} -body {
  db eval { CREATE VIRTUAL TABLE abc USING fts5(x,y) }
} -test {
  faultsim_test_result {0 {}}
}


#-------------------------------------------------------------------------
# OOM while writing a multi-tier doclist-index. And while running
# integrity-check on the same.
#
reset_db
do_execsql_test 2.0 {
  CREATE VIRTUAL TABLE tt USING fts5(x);
  INSERT INTO tt(tt, rank) VALUES('pgsz', 32);
}
faultsim_save_and_close

do_faultsim_test 2.1 -faults oom-t* -prep {
  faultsim_restore_and_reopen
  db eval { SELECT * FROM tt }
} -body {
  set str [string repeat "abc " 50]
  db eval {
    WITH ii(i) AS (SELECT 1 UNION ALL SELECT i+1 FROM ii WHERE i<100)
      INSERT INTO tt(rowid, x) SELECT i, $str FROM ii;
  }
} -test {
  faultsim_test_result {0 {}}
}

do_faultsim_test 2.2 -faults oom-t* -body {
  db eval { INSERT INTO tt(tt) VALUES('integrity-check') }
} -test {
  faultsim_test_result {0 {}}
}

#-------------------------------------------------------------------------
# OOM while scanning an fts5vocab table.
#
reset_db
do_test 3.0 {
  execsql {
    CREATE VIRTUAL TABLE tt USING fts5(x);
    CREATE VIRTUAL TABLE tv USING fts5vocab(tt, 'row');
    INSERT INTO tt(tt, rank) VALUES('pgsz', 32);
    BEGIN;
  }
  for {set i 0} {$i < 20} {incr i} {
    set str [string repeat "$i " 20]
    execsql { INSERT INTO tt VALUES($str) }
  }
  execsql COMMIT
} {}

do_faultsim_test 2.1 -faults oom-t* -body {
  db eval {
    SELECT term FROM tv;
  }
} -test {
  faultsim_test_result {0 {0 1 10 11 12 13 14 15 16 17 18 19 2 3 4 5 6 7 8 9}}
}



finish_test